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Could somebody explain what the pins on a 555 timer do please?

Hey guys, I have the general knowledge when it comes to creating schematics and all but I do not undertand how a 555 timer is supposed to work. I simply want to be able to control some oscillation using a pot/rheostat. I already have resistors, capacitors, transistors, a power supply and a speaker but I do not know how I should connect them. Can somebody please explain how it would work?

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iceng5 years ago
I think you will like this 555 PDF by Signetics.

A
dipseydoodle (author)  iceng5 years ago
So, tell me if I'm wrong... 1 need a negative line. 2 would get a positive line with a Pot, 3 would be a positive line. 4 would be a cap? Or am I all wrong?
  1. Ground ==  Zero reference Common.. .. Not negative
  2. Trigger_Pot_Cap
  3. Output ( goes positive {High}  then ground {Low} voltage ) 
  4. Reset_Not  usually tied to positive Supply voltage line
A
555-Pinout-3.GIF
rickharris5 years ago
data sheet

the 555 can be:

an Astable oscillator
or a one shot.

You can look these terms up.
Found this great site the other day which has a calculator so you know how the 555 timer will act with various resistors and capacitors on the appropriate pins. It also offers a breakdown of the pins and offers up a few 555 timer circuits to play with.
http://www.bowdenshobbycircuits.info/555.htm
http://en.wikipedia.org/wiki/555_timer_IC